This invention relates generally to precast concrete structural units for use in the construction of walls and the like in vertically stacked horizontal rows.
More particularly, the invention relates to an improved precast concrete structural unit of the general type shown in U.S. Pat. No. 3,877,236. The structural unit shown in this patent comprises a pair of spaced side panels and a laterally extending connecting arm for fixing the side panels in position. The units may be stacked one atop the other in staggered horizontal rows to form a wall. A lateral interlock means takes the form of depending marginal portions at lower edges of the panels which engage top edge portions of sub-adjacent units to secure the units against lateral displacement.
The units of the patent and composite wall structures constructed therewith are generally satisfactory. The structural integrity of the composite walls however, particularly in the case of retaining walls, may be inadequate in certain instances.
It is the general object of the present invention to provide an improved precast concrete structural unit of the type mentioned wherein the structural integrity of the individual unit is substantially improved with an attendant improvement in the structural integrity of a composite wall structure formed with a plurality of units stacked vertically in horizontal rows.